Field of the Invention
The present invention relates to a solid-state imaging device and a method of driving the solid-state imaging device.
Description of the Related Art
In recent years, imaging devices such as digital video camera, digital camera, and the like each using a CMOS image sensor suitable to realize a low electric power consumption and a high-speed read-out have widely and generally been spread. In the CMOS image sensor, the sequential read-out operation (rolling shutter operation) for sequentially reading out pixels every row or every block of a few rows is fundamentally executed. A CMOS image sensor having a function of a full-pixel simultaneous electronic shutter has also been proposed. Japanese Patent Application Laid-Open No. 2006-246450 discloses a technique for widening a dynamic range of the CMOS image sensor having the function of the full-pixel simultaneous electronic shutter.
The CMOS image sensor having the function of the full-pixel simultaneous electronic shutter has a charge accumulating portion for temporarily accumulating signal charges generated in a photodiode. A read-out period of the signal accumulated in the charge accumulating portion overlaps with an accumulating period of the signal charges into the photodiode for a next frame. However, if signal charges exceeding a saturation charge amount of the photodiode occur during the read-out period of the signal from the charge accumulating portion, since the signal charges over the saturation charge amount are thrown away, there is a case where a picture quality deteriorates.